Roland MT-90U Operating and maintenance manual

SERVICE NOTES
Issued by RJA
Copyright © 2008 Roland Corporation
All rights reserved. No part of this publication may be reproduced in any form without the written permission
of Roland Cororation.
Printed in Japan (0285) (CC-KWS)17058572E0
Mar. 2008 MT-90U
Table of Contents
Cautionary Notes ..............................................................2
Main Specifications ...........................................................2
Location of Controls (Front Panel) .................................4
Location of Controls (Front Panel) Parts List................4
Location of Controls (Rear Panel)...................................5
Location of Controls (Rear Panel) Parts List .................5
Exploded View (All) .........................................................6
Exploded View (All) Parts List........................................7
Exploded View (1).............................................................8
Exploded View (1) Parts List...........................................9
Exploded View (2)...........................................................10
Exploded View (2) Parts List.........................................10
Important Notes on Assembly ......................................11
Block Diagram/Wiring Diagram..................................14
Parts List ...........................................................................16
Verifying the Version Number......................................18
Performing a Factory Reset............................................18
Updating the System ......................................................18
Test Mode .........................................................................18
Circuit Board (Main Board) ...........................................22
Circuit Diagram (Main Board: 1/4)..............................24
Circuit Diagram (Main Board: 2/4)..............................26
Circuit Diagram (Main Board: 3/4)..............................27
Circuit Diagram (Main Board: 4/4)..............................28
Circuit Board (Panel Board)...........................................30
Circuit Diagram (Panel Board)......................................32
Circuit Board (Jack, Volume, IR, USB, Power SW
Board)................................................................................34
Circuit Diagram (Jack Board: 1/3)................................36
Circuit Diagram (Jack Board: 2/3)................................38
Circuit Diagram (Jack Board: 3/3)................................40
Circuit Diagram (Volume Board)..................................42
Circuit Diagram (IR Board)............................................44
Circuit Diagram (USB Board)........................................44
Circuit Diagram (Power SW Board) .............................45

2
Mar. 2008 MT-90U
Cautionary Notes
Before beginning the procedure, please read
through this document. The matters described may
differ according to the model.
Back Up User Data!
Executing a Factory Reset returns the following settings to their factory
defaults. These cannot be backed up. Note them down on paper as required.
• Tuning settings (Owner’s Manual p. 17)
• Metronome tone (Owner’s Manual p. 47)
• Count sound settings (Owner’s Manual p. 48)
• Lyrics-display language setting (Owner’s Manual p. 49)
• Track Assign settings (Owner’s Manual p. 50)
• Setting the Type and Timing of CD to be Played Back
(Owner’s Manual p.51)
• USB memory settings (Owner’s Manual p. 52)
• USB driver settings (Owner’s Manual p. 52)
Part Replacement
When replacing components near the power-supply circuit or a heat-
generating circuit (such as a circuit provided with a heat sink or including a
cement resistor), carry out the procedure according to the instructions with
respect to the part number, direction, and attachment position (mounting so as
to leave an air gap between the component and the circuit board, etc.).
Parts List
A component whose part code is ******** cannot be supplied as a service part
because one of the following reasons applies.
• Because it is supplied as an assembled part (under a different part code).
• Because a number of circuit boards are grouped together and supplied as
a single circuit board (under a different part code).
• Because supply is prohibited due to copyright restrictions.
• Because reissuance is restricted.
• Because the part is made to order (at current market price).
Circuit Diagram
In the circuit diagram, “NIU” is an abbreviation for “Not in Use,” and
“UnPop” is an abbreviation for “Unpopulated.” They both mean non-mounted
components. The circuit board and circuit board diagram show silk-screened
indications, but no components are mounted.
In the Main Board Circuit Diagram (p. 24), red parts on the PDF and gray parts
on paper media service notes mean non-mounted components. The circuit
board and circuit diagram show silk-screened indications, but no components
are mounted.
Main Specifications
MT-90U: Music Player
Playback Composer
External Memory
• USB Memory (sold separately)
• Floppy Disk
* Read only
* USB 3.5 in. floppy disk drive (FD-01 series) required (sold separately)
• CD-ROM
• Audio CD
* Read only
* Commercial USB CD drive required
Supported Data
• Standard MIDI Files (format 0/1)
• Roland Original Format
• Audio files (WAV; 44.1 kHz, 16 bit linear format)
• MP3 files (44.1 kHz, 32 to 320 kbps)
• Audio CD
* Commercial USB CD drive required
Tracks
16 tracks
Control
Reset, Stop, Play, Bwd, Fwd, Repeat, Marker, Song, Tempo, [+], [-], Track
Selection, Count In, Metronome (MIDI only), Center Cancel (audio only)
Tempo
Quarter note = 10 to 500 (MIDI only)
75 to 125% (audio only)
Resolution
120 ticks per quarter note (MIDI only)
Transpose
-6 to +5 (semitones)
Demo Songs
14 songs

3
Mar. 2008 MT-90U
Sound Generator
Max. Polyphony
128 voices (MIDI only)
Tones
348 tones (including 8 drum sets, 1 effects set)
Internal Sounds
Conforms to GM2 system/GS format/XGlite supported
Master Tuning
415.3 Hz to 466.2 Hz (0.1 Hz units)
Effects
Reverb (MIDI only)
Chorus (MIDI only)
Sound Control: Sharp, Clear, Power
Sequencer
Metronome
Time Signatures: 2/2, 0/4, 2/4, 3/4, 4/4, 5/4, 6/4, 7/4, 3/8, 6/8, 9/8, 12/8
Volume: 11 levels
Pattern: 11 patterns
Other Functions
• Infrared Transmission
• Mic Echo
• Song List
• Floppy Disk Backup
Others
Display
Beat Indicator
122 x 32 dot, Graphic LCD (with backlight)
Language
Japanese (song title, lyrics), English
Lyric Display
Yes (LCD display)
Controls
• Volume
• Mic volume
• Mic echo
• Speaker switch
Rated Power Output
5 W
Speakers
10 cm x 1
Connectors
External memory connector: USB type A
USB connector: USB type B
Output jack (R/L): RCA pin type
Microphone jack (Mono): Standard type
Headphones jack: Stereo, mini type
MIDI In connector
Start/Stop jack
Power Supply
DC9V
Current Draw
2000 mA
Dimensions
165 (W) x 186 (D) x 270 (H) mm
6-1/2 (W) x 7-3/8 (D) x 10-11/16 (H) inches
Weight
2.5 Kg / 5 lbs 9 oz
Accessories
AC Adaptor (#04236101)
Power Code for 120 V (#02562456)
for 220 V CN (#5100000564)
for 230 V E (#5100000115)
for 230 V EU (#01903356)
for 240 V A (#03785590)
Remote Control (#04898434)
Lithium Battery (CR2025) (#********)
Owner’s Manual English (#04787745)
Options
USB Memory (M-UF1GB)
Floppy Disk Drive (FD-01 series)
Roland Microphone (DR-10/20)
Pedal Switch (DP-2)
* In the interest of product improvement, the specifications and/or appearance of
this unit are subject to change without prior notice.

4
Mar. 2008 MT-90U
Location of Controls (Front Panel)
fig.FrontPanel.eps
Location of Controls (Front Panel) Parts List
1
7
10
9
2
3
8
11 12
6
5
4
No. Part Code Part Name Description Q’ty
1 04787512 DISPLAY COVER 1
04780545 LCD 221-3065-0784 1
2 04892901 RADIAL LED (2COLOR RED/GREEN) L-3749ESGC 1
3 04787623 R-KNOB MF 1
05017756 14MM ROTARY VOLUME (STEREO) F14KH-1 B10K L15 FCX7 1
4 04787612 RUBBER SWITCH 1
5 04787567 LED LENS 4P 1
6 04787590 LED LENS 5P 1
04780456 LED (RED) L-314ED 4
7 04787589 LED LENS 1P 1
02015623 LED (GREEN) SLR-342MG3F 6
8 02341689 3.5MM JACK HTJ-035-28 1
9 04787490 BUTTON 1
05017823 POWER SWITCH PWL-2P1TL-6SASTC-001 1
10 04787645 FRONT PANEL 1
11 04787556 IRDA COVER 1
04673667 INFRARED TRANSCEIVER MODULE TFDU4101-TT3 1
03342178 IC GP1UM261RK0F 1
12 04560101 USB CONNECTOR A TYPE FEMALE UAR27-4K5J00 1

5
Mar. 2008 MT-90U
Location of Controls (Rear Panel)
fig.RearPanel.eps
Location of Controls (Rear Panel) Parts List
2
1
3 4
87 9
6
5
10
No. Part Code Part Name Description Q’ty
1 02341634 DC JACK HTJ-020-05A (610-00100-04-00) 1
2, 8 00569278 6.5MM JACK LGR4609-7100F 2
3, 4 04890223 9MM VOLUME VX09211NPP20U1B20K 2
5 04890689 SLIDE SWITCH SKA-22D01N-G6-NA 1
6 05014890 PIN JACK 2L2P WR NI HSP-242V1P-01 1
7 03909767 DIN CONNECTOR HDC-052A-11 1
9 01459945 USB CONNECTOR YKF45-0002 1
10 40454856 SCREW M4X10 BINDING NI 1

6
Mar. 2008 MT-90U
Exploded View (All)
fig.bunkaizu-all.eps
View3View4
View5
View1
View2
View9
View8
View6
View7
5
19
17
18 10
11
12
4
13
6
7
14
9
15
16
1
20
3
2
8

7
Mar. 2008 MT-90U
Exploded View (All) Parts List
No. Part Code Part Name Description Q’ty
1 04787601 REAR CASE 1
2 04787534 FRONT CASE 1
3 02342712 SPEAKER FULL-RANGE 1
4 04780545 LCD 221-3065-0784 1
5 04787634 SP GRILLE + NET 1
6 04787556 IRDA COVER 1
7 04898312 IR BOARD ASSY 1
8 04898334 VOLUME BOARD ASSY 1
9 04898367 SW BOARD ASSY 1
10 05122112 FRONT PANEL WITH LED LENS 1
11 04787612 RUBBER SWITCH 1
12 04898378 PANEL BOARD ASSY 1
13 04787501 CHASSIS 1
14 04898301 USB BOARD ASSY 1
15 04785823 MAIN BOARD ASSY 1
16 04898290 JACK BOARD ASSY 1
17 04787623 R-KNOB MF 1
18 04787490 BUTTON 1
19 04787512 DISPLAY COVER 1
20 01235378 FOOT 4

8
Mar. 2008 MT-90U
Exploded View (1)
fig.bunkaizu-1.eps
b
a
f
a
f
f
c
f
e
View1 View2
View3 View4
View5 View6

9
Mar. 2008 MT-90U
Exploded View (1) Parts List
View 1, 2
View 3, 4
View 5, 6
No. Part Code Part Name Description Q’ty
a 40011312 SCREW 3X8 BINDING TAPTITE P BZC 5
b 40012490 SCREW 4X10 BINDING TAPTITE P BZC 4
c 40011334 SCREW 3X12 BINDING TAPTITE-P FE BZC 1
e 40454856 SCREW M4X10 BINDING NI 1
f 03904456 SCREW 3X6 B-TITE BIND BZC 4
No. Part Code Part Name Description Q’ty
f 03904456 SCREW 3X6 B-TITE BIND BZC 8
No. Part Code Part Name Description Q’ty
a 40011312 SCREW 3X8 BINDING TAPTITE P BZC 6
f 03904456 SCREW 3X6 B-TITE BIND BZC 2

10
Mar. 2008 MT-90U
Exploded View (2)
fig.bunkaizu-2.eps
Exploded View (2) Parts List
View 7, 8, 9
ab
a
d
a
a
View7 View8
View9
No. Part Code Part Name Description Q’ty
a 40011312 SCREW 3X8 BINDING TAPTITE P BZC 19
b 40012490 SCREW 4X10 BINDING TAPTITE P BZC 4
d 40012867 SCREW M3X8 PAN MACHINE W/SW+PW ZC 2

11
Mar. 2008 MT-90U
Important Notes on Assembly
To prevent damage to the wiring, cover edges using acetate tape.
fig.kumitate-1.eps
fig.kumitate-2.eps
To prevent screeching (unpleasant noise caused by vibration), apply acetate
tape having a width of 10 mm to the front case.
fig.kumitate-3-e.eps
fig.kumitate-4-e.eps
10 mm 10 mm
25 mm 25 mm
10 mm
10 mm
10 mm
10 mm
Apply 2 overlapping strips. Apply 2 overlapping strips.
Apply 1 strip.
Apply 1 strip.
Not OKOK
Acetate tape
Front case

12
Mar. 2008 MT-90U
To prevent dust entry, apply cushion tape to the LCD unit. Do not peel off the
backing paper.
fig.kumitate-5-e.eps
To prevent light leakage by the LCD backlight from the speaker grille, apply
acetate tape having a width of 12 mm.
fig.kumitate-6.eps
fig.kumitate-7-e.eps
Secure the LCD wiring in place on the back of the front case using acetate tape.
fig.kumitate-8.eps
fig.kumitate-9-e.eps
Secure the IrDA cover in place using double-sided adhesive tape having a
width of 5 mm.
fig.kumitate-10.eps
fig.kumitate-11.eps
Do not peel off
the backing paper.
Not OK
Not OK

13
Mar. 2008 MT-90U
As a measure to prevent electromagnetic interference (EMI), attach Wiring J-2
to the Volume Board. Be careful to attach at the correct angle.
fig.kumitate-12.eps
fig.kumitate-13-e.eps
Apply cushion tape for protecting the wiring to the Jack Board. Take care not
to cover the screw hole.
fig.kumitate-14.eps
Twist the 9-pin wiring connecting the Jack Board and Volume Board 3 turns.
fig.kumitate-15-e.eps
Also secure the 9-pin wiring and 3-pin wiring using a sub-tie.
fig.kumitate-16.eps
To keep the volume control from coming loose, apply double-sided adhesive
tape having a width of 5 mm to the volume shaft.
fig.kumitate-17.eps
fig.kumitate-18-e.eps
Attachment angle
not OK
20mm
Twist 3 turns.
3-pin
9-pin
Volume control
Double-sided
adhesive tape

14
Mar. 2008 MT-90U
Block Diagram/Wiring Diagram
fig.block.eps@L
W1
W2
W3
W4

15
Mar. 2008 MT-90U
fig.block.eps@R
W5 W6
W7
W8
W9
W10
W11
No. Part Code Part Name Description Q’ty
W1 04894167 WIRING SW 2P L=120 UL1061 AWG22 VHR 1
W2 05012456 WIRING J-2 1
W3 04894145 WIRING 3P L=50 UL1061 AWG26 PHR-PHR 1
W4 05012067 WIRING J-1 1
W5 04894156 WIRING USB 5P L=130 UL20276 PHR-PHR 1
W6 04894134 WIRING 6P L=90 UL1061 AWG26 PHR-PHR 1
W7 04894201 WIRING FFC 20624FWRP1.00K1(0.05 x 0.7)20 1
W8 05011167 WIRING SHIELD 3P L=100 UL2791 AWG28 PHR-PHR 1
W9 04894178 WIRING SP 2P L=100 UL1061 AWG20 XHP 1
W10 04894189 WIRING FFC 20624FWRP1.00K1(0.05 x 0.7)16 1
W11 04894190 WIRING FFC 20624FWRP1.25K1(0.05 x 0.8)18 1

16
Mar. 2008 MT-90U
Parts List
fig.-part1-e.eps
SAFETY PRECAUTIONS:
The parts marked have
safety-related characteristics. Use
only listed parts for replacement.
NOTE: The parts marked # are new. (initial parts)
Due to one or more of the following reasons,
parts with parts code ******** cannot be supplied as service parts.
• Part supplied only as a component in a complete assembly
• Copyright does not permit the part to be supplied
• Part is sold commercially
The description "Q'TY" means a necessary number of the parts per one product.
CASING
# 04787501 CHASSIS 1
# 04787512 DISPLAY COVER 1
# 04787534 FRONT CASE 1
# 04787556 IRDA COVER 1
# 04787601 REAR CASE 1
# 04787634 SP GRILLE + NET 1
# 04787645 FRONT PANEL 1
# 05122112 FRONT PANEL WITH LED
LENS
1
KNOB, BUTTON
# 04787490 BUTTON 1
# 04787623 R-KNOB MF 1
SWITCH
# 04787612 RUBBER SWITCH 1
# 04890689 SLIDE SWITCH SKA-22D01N-G6-NA SW2 on Jack Board 1
# 05017823 POWER SWITCH PWL-2P1TL-6SASTC-001 SW401 on Power SW Board 1
JACK, EXT TERMINAL
00569278 6.5MM JACK LGR4609-7100F JK2 on Jack Board, JK4 on Main Board 2
01459945 USB CONNECTOR YKF45-0002 JK2 on Main Board 1
02341634 DC JACK HTJ-020-05A (610-00100-04-00) JK1 on Jack Board 1
02341689 3.5MM JACK HTJ-035-28 JK301 on Volume Board 1
03909767 DIN CONNECTOR HDC-052A-11 JK3 on Main Board 1
# 05014890 PIN JACK 2L2P WR NI HSP-242V1P-01 JK3 on Jack Board 1
04560101 USB CONNECTOR A TYPE FE-
MALE
UAR27-4K5J00 JK201 on USB Board 1
DISPLAY UNIT
04780545 LCD 221-3065-0784 1
SPEAKER, BUZZER
02342712 SPEAKER FULL-RANGE 1
PWB ASSY
# 04785823 MAIN BOARD ASSY 1
# 04898290 JACK BOARD ASSY 1
# 04898301 USB BOARD ASSY 1
# 04898312 IR BOARD ASSY 1
# 04898334 VOLUME BOARD ASSY 1
# 04898367 SW BOARD ASSY 1
# 04898378 PANEL BOARD ASSY 1
IC
03342178 IC GP1UM261RK0F CN102 on IR Board 1
# 04673667 INFRARED TRANSCEIVER
MODULE
TFDU4101-TT3 IC101 on IR Board 1
DIODE
02015623 LED (GREEN) SLR-342MG3F LED5, LED6, LED7, LED8, LED9, LED10 on
Panel Board
6
04780456 LED (RED) L-314ED LED, LED2, LED3, LED4 on Panel Board 4
# 04787567 LED LENS 4P 1
# 04787589 LED LENS 1P 1
# 04787590 LED LENS 5P 1
# 04892901 RADIAL LED (2COLOR RED/
GREEN)
L-3749ESGC LED301 on Volume Board 1

17
Mar. 2008 MT-90U
POTENTIOMETER
# 04890223 9MM VOLUME VX09211NPP20U1B20K VR1, VR2 on Jack Board 2
# 05017756 14MM ROTARY VOLUME
(STEREO)
F14KH-1 B10K L15 FCX7 VR301 on Volume Board 1
WIRING, CABLE
# 04894134 WIRING 6P L=90 UL1061 AWG26 PHR-
PHR
1
# 04894145 WIRING 3P L=50 UL1061 AWG26 PHR-
PHR
1
# 04894156 WIRING USB 5P L=130 UL20276 PHR-PHR 1
# 04894167 WIRING SW 2P L=120 UL1061 AWG22
VHR
1
# 04894178 WIRING SP 2P L=100 UL1061 AWG20 XHP 1
# 04894189 WIRING FFC 20624FWRP1.00K1(0.05 x 0.7)16 1
# 04894190 WIRING FFC 20624FWRP1.25K1(0.05 x 0.8)18 1
# 04894201 WIRING FFC 20624FWRP1.00K1(0.05 x 0.7)20 1
# 05011167 WIRING SHIELD 3P L=100 UL2791 AWG28 PHR-
PHR
1
# 05012067 WIRING J-1 1
# 05012456 WIRING J-2 1
SCREWS
03904456 SCREW 3X6 B-TITE BIND BZC 14
40011312 SCREW 3X8 BINDING TAPTITE P BZC 30
40011334 SCREW 3X12 BINDING TAPTITE-P FE BZC 1
40012490 SCREW 4X10 BINDING TAPTITE P BZC 8
40012867 SCREW M3X8 PAN MACHINE W/SW+PW
ZC
2
40012878 SCREW M3X10 PAN MACHINE W/SW+PW
ZC
1
40454856 SCREW M4X10 BINDING NI 1
MISCELLANEOUS
01235378 FOOT 4
# 5100000542 LABEL ADHES NAMEPLATE CCC for China 1
ACCESSORIES (Standard)
# 04898434 REMOTE CONTROL UNIT 1
04236101 AC ADAPTOR WITHOUT AC
CORD
PSB-1U(S) UNIVERSAL 1
01903334 AC CORD SET PSE 100V 1.0M FOR PSB-1U for 100V 1
02562456 AC CORD SET 120V 1.0M (NON POLAR) for 117V 1
5100000564 AC CORD (CCC) 220V CN for 220VCN 1
01903356 AC CORD SET 230V 1.0M FOR PSB for 230VEU 1
5100000115 AC CORD SET 230VE 1.0M FOR
PS
for 230VE 1
03785590 AC CORD SET SC-078-NA05 240VA for 240VA 1
# 04787734 NIHONGO PANEL SHEET for Japan Only 1
# 04787745 OWNER’S MANUAL ENGLISH 1
# 04787801 OWNER’S MANUAL JAPANESE 1
40232334 WARRANTY CARD MOCHIKOMI JAPAN ONLY 1

18
Mar. 2008 MT-90U
Verifying the Version
Number
1. Hold down the [1] button and the [ ] button and switch on the power.
The version number appears on the screen.
2. After carrying out verification, switch off the power.
Performing a Factory Reset
Executing a Factory Reset returns the following settings to their factory
defaults. These cannot be backed up. Note them down on paper as required.
• Tuning settings (Owner’s Manual p. 17)
• Metronome tone (Owner’s Manual p. 47)
• Count sound settings (Owner’s Manual p. 48)
• Lyrics-display language setting (Owner’s Manual p. 49)
• Track Assign settings (Owner’s Manual p. 51)
• USB memory settings (Owner’s Manual p. 52)
• USB driver settings (Owner’s Manual p. 52)
1. Hold down [ ] and press [4].
The Function screen appears.
2. Press [ ] or [ ] to display a screen like the one shown below.
fig.factory-reset-ok.eps
To cancel the factory reset, press [ ].
3. Press [+].
The screen shown below appears and the [ ] light flashes.
fig.factory-reset-sure.eps
To cancel the Factory Reset, press [ ].
4. Pressing [ ] executes the Factory Reset.
5. Turn the power off, then back on.
Updating the System
1. Unarchive the update file, then copy all files and folders to the root folder
on a USB memory device.
2. Load the USB memory device in the MT-90U.
3. Hold down the [ ] and [ ] buttons and switch on the power.
The update starts automatically.
* Never switch off the power while the update is in progress.
When the message Complete appears, the update has finished.
4. Switch off the power and detach the USB memory device.
5. Execute a Factory Reset.
Test Mode
Items Required
• MT-90U
• AC Adapter: PSB-1U and power cord (included)
• Remote Controller for the MT-90U (included)
• Headphones
• MIDI Keyboard
• Microphone
• Monitor Speaker (with amp)
• Noise Meter
• Pedal Switch
• USB Memory Device (128 MB or larger, containing an MP3 file)
Entering the Test Mode
Hold down the [R] and [ ] buttons and switch on the power.
Quitting the Test Mode
Switch off the power.
Selecting Test Items
1. Hold down the [ ] button and press the [ ] button.
The Test menu appears.
2. Use [ ] and [ ] to choose the test item you want to execute.
3. Press [ ].
Test Items
1. Version (p. 19)
2. Device Test (p. 19)
3. USB Test (p. 19)
4. IrDA Test (p. 19)
5. Switch Test (p. 19)
6. Red LED Test (p. 19)
7. Green LED Test (p. 19)
8. LCD Test (p. 19)
9. Volume Test (p. 20)
10. MIDI Test (p. 20)
11. Noise Test (p. 20)
12. Mic Test (p. 20)
13. Phase Test (p. 20)
14. Echo Test (p. 20)
15. Factory Reset (p. 20)
Test Items Outside the Test Mode
Speaker Test (p. 21)
Headphones Test (p. 21)
External Speaker Test (p. 21)

19
Mar. 2008 MT-90U
1. Version
Verify the version of the system.
1. Hold down the [R] and [ ] buttons and switch on the power.
The Test mode is enabled.
2. Verify that [SYS] has been selected and press the [ ] button.
fig.test-Version.eps
3. Verify that the unit is at the latest version.
4. Press the [ ] button to advance to the next item.
2. Device Test
This automatically checks the operation of the Wave ROM.
fig.test-Device-1.eps
fig.test-Device-2.eps
When OK is displayed, press the [ ] button to advance to the next
item.
3. USB Test
This performs a USB connection check.
1. Using a USB cable, connect the USB connector on the front panel to the
USB connector on the rear panel.
2. Verify that the message displayed on the LCD screen changes from
Disconnected to Connected.
fig.test-USB-1.eps
fig.test-USB-2.eps
If no problem is found, execution automatically advances to the next
item.
4. IrDA Test
This performs testing of infrared communication.
* Outside Japan, this test is not required. Press the [ ] button to advance to the
next item.
fig.test-IrDA.eps
5. Switch Test
This tests switch operation.
1. Press the [ ], [ ], [-], and [+] buttons on the front panel in
sequence, one at a time, and verify that each button name is displayed on
the LCD screen.
2. Connect the pedal switch to the Start/Stop jack on the rear panel.
3. Depress the pedal and verify that the message Pedal is displayed on the
LCD screen.
fig.test-Switch-1.eps
4. Aim the remote-control unit at the infrared port on the front panel.
5. Press the [REPEAT] button on the remote control and verify that the
message RemoteRepeat is displayed on the LCD screen.
fig.test-Switch-2.eps
When verification for all switches has finished, execution automatically
advances to the next item.
6. Red LED Test
This tests illumination of the red LEDs.
1. Press the [ ], [ ], [ ], and [ ] buttons in sequence, one
at a time.
2. Verify that the corresponding LED for each lights up.
3. Press the [ ] button.
4. Verify that the Beat LED (to the left of the LCD screen) lights up.
When verification for all red LEDs has finished, execution automatically
advances to the next item.
7. Green LED Test
This tests illumination of the green LEDs.
1. Press the [R], [1], [2], [3], [4], and [ ] buttons in sequence, one at a time.
2. Verify that the corresponding LED for each lights up.
3. Press the [ ] button.
4. Verify that the Beat LED (to the left of the LCD screen) lights up.
When verification for all green LEDs has finished, execution
automatically advances to the next item.
8. LCD Test
This tests the display of the LCD screen.
fig.test-LCD.eps
1. Verify that pressing the [ ] button makes the entire screen go dark
and that pressing the [ ] button makes the entire screen light up.
2. Press the buttons just described in alternation and verify that no dot
drop-out is present.
3. Press the [ ] button to advance to the next item.

20
Mar. 2008 MT-90U
9. Volume Test
This tests the volume controls.
fig.test-Volume-1.eps
1. Turn the Mic Echo control on the rear panel and verify that the value of
Echo displayed on the LCD screen changes from 0to 127.
fig.test-Volume-2.eps
2. Turn the Mic Volume control and verify that the value of Mic displayed
on the LCD screen changes from 0to 127.
fig.test-Volume-3.eps
3. Turn the Volume control on the front panel and verify that the value of
Master displayed on the LCD screen changes from 0to 127.
fig.test-Volume-4.eps
When verification for all volume controls has finished, execution
automatically advances to the next item.
10. MIDI Test
fig.test-MIDI.eps
1. Connect the MIDI keyboard to MIDI IN on the rear panel, play the
keyboard, and verify that the MT-90U produces sound.
2. Press the [ ] button to advance to the next item.
11. Noise Test
fig.test-Noise.eps
1. Connect the noise meter to the Output jack on the rear panel.
2. Make settings like those shown below, then measure the noise level on
both the left and right.
Volume: Max
Mic Volume: Min
Mic Echo: Min
Noise meter: DIN AUDIO
The noise levels are acceptable if at -80 dBm or lower on both the left and
right.
3. Press the [ ] button to advance to the next item.
12. Mic Test
fig.test-Mic.eps
1. Connect the microphone to Mic In and make settings like those shown
below.
Volume: Max
Mic Volume: Max
2. Input vocals via the microphone and verify that sound is heard from the
speaker.
3. Press the [ ] button to advance to the next item.
13. Phase Test
This test is required only at the time of shipment from the factory. Press the
[ ] button to advance to the next item.
14. Echo Test
fig.test-Echo.eps
1. Connect the microphone to Mic In and make settings like those shown
below.
Volume: Middle position
Mic Volume: Middle position
2. Input vocals via the microphone and verify that no echo is applied.
3. Increase the Echo level to Max.
4. Input vocals via the microphone and verify that echo is applied.
5. Press the [ ] button to advance to the next item.
15. Factory Reset
fig.test-FctRst-1.eps
1. Press the [ ] button to select OK, then press [ ].
A factory Reset is executed.
fig.test-FctRst-2.eps
After a short interval, the message Completed appears, then the message
End is displayed.
fig.test-FctRst-3.eps
fig.test-FctRst-4.eps
2. Switch off the power.